The Internal Revenue Service on Wednesday revealed a way taxpayers can prepay 2018 state and local property taxes before a deduction next year is reined in by the new Republican tax reform plan.

This would allow property owners to skirt around the $10,000 cap that will be instituted by the tax overhaul that was just signed into law by President Trump.

But while the workaround is applicable to 2017 federal income returns, it will only apply in very specific and time-sensitive circumstances, an advisory from the IRS said.

Taxpayers must pay the tax this year, creating an immediate deadline as the new year approaches in just a couple of days.

A property also needs to be assessed, which means a tax authority has to have informed owners how much in property taxes they owe before they pay. Estimates do not apply. Also, different local and state tax authorities in different locations notify taxpayers of this assessment at varying times – which could mean some Americans are out of luck.

The IRS announcement follows New York Gov. Andrew Cuomo signing an order that was designed to allow New Yorkers benefit from the deduction, circumventing the Republican bill that he said was made to hurt blue states. Under that order, partial or full payment of property taxes would also have to have been made before Jan. 1.